Questions tagged [regex]
Regular expressions provide a declarative language to match patterns within strings. They are commonly used for string validation, parsing, and transformation. Specify the language (PHP, Python, etc) or tool (grep, VS Code, Google Analytics, etc) that you are using. Do not post questions asking for an explanation of what a symbol means or what a particular regular expression will match.
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RegEx match open tags except XHTML self-contained tags
I need to match all of these opening tags:
<p>
<a href="foo">
But not self-closing tags:
<br />
<hr class="foo" />
I came up with this and wanted to make ...
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Reference - What does this regex mean?
What is this?
This is a collection of common Q&A. This is also a Community Wiki, so everyone is invited to participate in maintaining it.
Why is this?
regex is suffering from give me ze code type ...
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How can I validate an email address using a regular expression?
Over the years I have slowly developed a regular expression that validates most email addresses correctly, assuming they don't use an IP address as the server part.
I use it in several PHP programs, ...
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My regex is matching too much. How do I make it stop? [duplicate]
I have this gigantic ugly string:
J0000000: Transaction A0001401 started on 8/22/2008 9:49:29 AM
J0000010: Project name: E:\foo.pf
J0000011: Job name: MBiek Direct Mail Test
J0000020: Document 1 - ...
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Learning Regular Expressions [closed]
I don't really understand regular expressions. Can you explain them to me in an easy-to-follow manner? If there are any online tools or books, could you also link to them?
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How can I validate an email address in JavaScript?
I'd like to check if the user input is an email address in JavaScript, before sending it to a server or attempting to send an email to it, to prevent the most basic mistyping. How could I achieve this?...
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Regular expression to match a line that doesn't contain a word
I know it's possible to match a word and then reverse the matches using other tools (e.g. grep -v). However, is it possible to match lines that do not contain a specific word, e.g. hede, using a ...
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What is a non-capturing group in regular expressions?
How are non-capturing groups, i.e., (?:), used in regular expressions and what are they good for?
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How to validate phone numbers using regex
I'm trying to put together a comprehensive regex to validate phone numbers. Ideally it would handle international formats, but it must handle US formats, including the following:
1-234-567-8901
1-234-...
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How to use Regular Expressions (Regex) in Microsoft Excel both in-cell and loops
How can I use regular expressions in Excel and take advantage of Excel's powerful grid-like setup for data manipulation?
In-cell function to return a matched pattern or replaced value in a string.
...
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What special characters must be escaped in regular expressions?
I am tired of always trying to guess, if I should escape special characters like '()[]{}|' etc. when using many implementations of regexps.
It is different with, for example, Python, sed, grep, awk, ...
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Using regular expressions to parse HTML: why not?
It seems like every question on stackoverflow where the asker is using regex to grab some information from HTML will inevitably have an "answer" that says not to use regex to parse HTML.
Why not? I'm ...
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Is there a RegExp.escape function in JavaScript?
I just want to create a regular expression out of any possible string.
var usersString = "Hello?!*`~World()[]";
var expression = new RegExp(RegExp.escape(usersString))
var matches = "...
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What is the best regular expression to check if a string is a valid URL?
How can I check if a given string is a valid URL address?
My knowledge of regular expressions is basic and doesn't allow me to choose from the hundreds of regular expressions I've already seen on the ...
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Why does a RegExp with global flag give wrong results?
What is the problem with this regular expression when I use the global flag and the case insensitive flag? Query is a user generated input. The result should be [true, true].
var query = 'Foo B';
var ...
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